Radioimmunoconjugates can be used in diagnostic and therapeutic medical procedures. Radiopharmaceuticals can carry at least one radionuclide bound to a carrier, for example a targeting moiety. The radionuclide can produce a signal detectable by radiological diagnostic equipment. Because the radiation emitted by the radionuclide can have a toxic effect on tissues, the radioimmunoconjugates can be utilized to achieve one or more therapeutic effects. When used as a therapeutic agent, localization of the radioimmunoconjugates at a specific structure or site in the body can be used to concentrate the effects of the radioimmunoconjugate in a structures or sites to be treated and can reduce harmful effects at other structures and sites in the body. For example, a radioimmunoconjugate may be used as a chemotherapy drug to kill cancerous tissues. There is a need for improved methods for the production of radioimmunoconjugates. This invention addresses this need.